Cooking fire suppression cover

ABSTRACT

This invention relates to a lightweight, thin, flexible fabric for a cooking fire suppression cover comprising a woven core of fiberglass mesh coated on its top and bottom surfaces with aluminized silicone for use in suppressing and/or extinguishing over a period of time relatively small initially contained fires, such as cooking fires on a stove.

FIELD OF THE INVENTION

This invention relates to cooking fire suppression covers for use in suppressing and/or extinguishing over a period of time relatively small initially contained fires, such as cooking fires on a stove or fires in small kitchen appliances. The suppression covers are intended to starve the fire of oxygen and thereby prevent its spread or enlargement until professional fire services arrive to extinguish it.

BACKGROUND OF THE INVENTION

Cooking oil or fat fires on a stove are a common source of fire in the home. Kitchen fires are the largest single cause of home fires and fire injuries in the United States. They account for more than 400 fatalities and 5,000 reported injuries annually. The cost of kitchen fires in the United States from 2004 through 2009 was on the order of one billion dollars annually during this period. These fires are particularly dangerous because the temperature of the underlying oil may be above its auto-ignition temperature. Thus, cooking oil fires may reignite when oxygen becomes available, even after initially extinguishing the fire. Furthermore, most conventional suppression compounds such as water, CO² foam or multi-purpose dry chemicals, are ineffective against cooking oil fires.

The conventional approach to extinguishing cooking oil fires is to use a fire blanket of intumescent material. Such fire blankets rely on the exclusion of oxygen to extinguish the fire. Often, due to the high temperatures involved (up to 360° C.) these fire blankets are made of woven glass fibers. Fire blankets may also be coated to exclude air, but should be flexible enough to form a seal about the fire to inhibit the availability of oxygen to the fire and hot oil in the cooking vessel.

Existing fire blankets have several problems. Where blankets are uncoated, the exclusion of oxygen relies entirely on the quality of the weave of the blanket. Any defects in the weave render the blanket less effective in excluding oxygen and may allow oil vapor to escape above the blanket where it may auto-ignite. Where a fire blanket coating is used, the coated fire blanket tends to be stiffer than a similar uncoated blanket, which reduces its effectiveness in sealing the periphery of the vessel and in containing the fire and excluding its oxygen supply.

The prior art reflects the means and methods that have been developed over the years for suppressing fires and preventing their spread, including those that use a smothering technique such as that used in fire blankets. One such example is U.S. Pat. No. 6,102,128, for a fire blanket that has been sold commercially under the name Kovenex®, which discloses an uncoated woven heat insulating fabric comprised of fire-resistant organic fibers, including melamine and melamine-formaldehyde based resins, polyamides, aramids and acrylic fibers. Another such example is U.S. Pat. No. 6,983,805, which discloses a type of fire blanket comprising a generally flexible substrate and a chemical compound, such as an alkali metal salt, which reacts endothermically when heated. U.S. Pat. No. 8,007,888 discloses a fire protection blanket comprising at least two fibrous subassemblies comprising at least two mineral fiber wool layers separated by at least one mineral fiber fabric, in which refractory particles are arranged. U.S. Pat. No. 8,272,450 discloses a fire blanket with handles comprising poorly flammable or inflammable blanket material, such as woven glass fiber with or without a fire resistant coating. U.S. Pat. No. 8,729,155 discloses an intumescent material comprising a substantial proportion of high temperature resistant inorganic fibers, such as high alumina polycrystalline fibers, glass fibers, quartz fibers, silica fibers, and the like. Additionally, there are a number of fire suppression type blankets on the market that utilize similar materials of construction, including those sold by American Safety Vest Company, with a non-woven fabric of flame resistant and organic fibers, and Chubb Home Products, with a woven fiberglass fire resistant fabric. None of these examples of types of fire blankets and other flame resistant materials has the lightweight, highly flexible properties of the present invention, which provides excellent flame suppressing and/or fire extinguishing properties in a woven fiberglass fabric blanket-type product.

SUMMARY OF THE INVENTION

In accordance with the invention, there is provided a relatively thin, lightweight, flexible intumescent fire suppression blanket-type cooking fire cover, comprising a woven fiberglass mesh coated on both sides with aluminized silicone. The silicone coating provides an excellent barrier to oxygen, which must be excluded from the fire. When the fire suppression cover is draped over a cooking fire on a stove or a small appliance such as a toaster, for example, it will prevent its spread and smother and/or extinguish the fire over a period of time. The flexibility and lightweight properties of the cover also allow for its ease of folding and storing in a pouch or package that can be placed in an easily accessible location until needed.

BRIEF DESCRIPTION OF THE DRAWINGS

The features and advantages of the invention will become apparent when considered in conjunction with the accompanying drawings, in which:

FIG. 1 is a top view of the fire suppression cover;

FIG. 2 is an enlarged cross-sectional view (not to scale) of the fire suppression cover showing the woven fiberglass core with the aluminized silicone coatings on top and bottom surfaces; and

FIG. 3A is an perspective of a typical cooking fire on a stove; and

FIG. 3B how the fire suppression cover is draped over a fire to suppress and/or extinguish it.

DETAILED DESCRIPTION OF THE INVENTION

The fire suppression cover is a lightweight, thin, highly flexible blanket-type fire cover comprising a woven core of fiberglass mesh that is coated on both top and bottom surfaces with aluminized silicone. As shown in FIG. 1, the fabric cover 10, has a smooth top surface 1 and smooth bottom surface (not shown) of aluminized silicone. FIG. 2 is a greatly enlarged cross-sectional view of the fabric as shown in FIG. 1, which shows the mesh core of woven fiberglass 2, with the aluminized silicone coatings coated on its top 3 and bottom 4 surfaces. FIG. 3A is an illustration of a cooking fire on a stove, and FIG. 3B shows the method of use of the product in draping it over a fire so as to smother and/or extinguish it.

The core of woven fiberglass mesh weighs between 6 and 10 ounces per square yard. The aluminized silicone coating is applied to the top and bottom surfaces of the fiberglass core at a rate of between 4 and 6 fluid ounces per yard of material. The coating may be applied by “knife over roll” or a “dip” process at a rate of less than 3 fluid ounces per side on both sides of the fiberglass mesh. Each coating layer is then polymerized by the application of heat at a temperature of at least 300° F. for 2 minutes. Each of the aluminized silicone coating layers of the finished product has a thickness of from about 0.5 mils to about 1.0 mils (0.0005 inches to about 0.001 inches). The woven fiberglass mesh of the type used in the invention is designated as Style 7628 8HS, provided by BGF Industries. The woven fiberglass fabric has a weave of from 55 to 59 ends/picks per inch. The silicone coatings are supplied by Wacker Chemicals as LR6200 series. The finished material has a total thickness of from about 6 mils to about 10 mils (about 0.006 inches to about 0.010 inches). The finished material will not ignite and will withstand flames in excess of 1800° F.

The finished cooking fire cover of this invention has a tensile strength of from 400-800 pounds per square inch in the warp direction and from 200-600 pounds per square inch in the fill direction. This combination of materials provides sufficient thinness and flexibility to allow it to be folded into a small package without crimping or damage to the product. The product's thinness and flexibility provides it with superior drapeability, making it capable of conforming to the various shapes of normal stove top cookware and small cooking appliances, such as toasters and toaster ovens. Drapeability is also important in the operation of the cover and its ability to suppress and/or extinguish a fire by excluding oxygen from the fire and allowing the burning materials to cool down below their auto-ignition point.

The finished product, in a preferred embodiment, measures 36 inches by 36 inches (1296 square inches), The weight of the finished material is between 11 and 15 ounces per square yard, which allows it to occupy a space of less than 9 inches by 5 inches by 1.5 inches. This permits the fire cover to be stored in a relatively small, compact package, such as one that is only 10 inches by 5.25 inches by 2 inches. The fire cover fabric plus its packaging weighs less than 16 ounces in total, allowing it to be mounted in a kitchen cabinet or drawer with double sided adhesive tape or other suitable means of attachment. This is an important safety feature of the invention since its storage at a location close to a fire and its ease of removal from the package allows for speedy use in an emergency.

The cooking fire cover of this invention has passed several standard tests for its effectiveness in suppressing and/or extinguishing small, contained cooking fires, including: (1) European Standard BS EN 1869:1997, “Fire Blankets,” a “Fire Performance Test” in which a 14 inch diameter pan with 3 liters of cooking oil is heated to 625° F., ignited and allowed to burn freely for 2 minutes; the flaming oil is then covered with a blanket. To pass the test the fire must be extinguished at 17 minutes after ignition. Three repetitions of the test are required to pass; (2) ASTM F 1989-05, “Standard Specification for Cooking Fire Suppression Blankets,” a “Home Cooking Fire Test,” in which a standard commercial cooing pan, on a standard range burner, is half-filled with cooking oil, ignited, allowed to burn freely for 1 minute, and then covered with a blanket. The fire must be extinguished at 3 minutes after ignition. Three repetitions of the test are required to pass. Additional tests passed by the cooking fire cover of this invention include: (3) the ASTM E 84/UL723, “Flame Spread and Smoke Generation,” Class A commercial (flame spread 5, Smoke index of 10; (4) the NFPA 701-10 Test 1, “Standard Methods—Flame Propagation of Textiles and Films;” and (5) the ASTM D 6413 “Vertical Flammability.”

In the foregoing description, it will be readily appreciated by those skilled in the art that modifications may be made to the invention without departing from the concepts disclosed herein. Such modifications are to be considered as included in the foregoing description. 

The invention claimed is:
 1. A flexible fire suppressing intumescent fabric comprising: a woven fiberglass core coated on top and bottom surfaces thereof with aluminized silicone.
 2. The flexible fire suppressing intumescent fabric of claim 1, having a thickness of from about 0.006 inches to about 0.010 inches.
 3. The flexible fire suppressing intumescent fabric of claim 1, in which each of the aluminized silicone coating layers has a thickness of from about 0.0005 inches to about 0.001 inches.
 4. The flexible fire suppressing intumescent fabric of claim 1, in which the weight of the fabric in a square of 36 inches by 36 inches is between 11 and 15 ounces per square yard of material.
 5. The flexible fire suppressing intumescent fabric of claim 1, in which the core of woven fiberglass is a weave having between 55 and 59 ends/picks per inch. 